Package org.apache.hadoop.ozone.om.ratis

Class OzoneManagerDoubleBuffer

java.lang.Object

org.apache.hadoop.ozone.om.ratis.OzoneManagerDoubleBuffer

public final class OzoneManagerDoubleBuffer
extends Object

This class implements DoubleBuffer implementation of OMClientResponse's. In DoubleBuffer it has 2 buffers one is currentBuffer and other is readyBuffer. The current OM requests will always be added to currentBuffer. Flush thread will be running in background, it checks if currentBuffer has any entries, it swaps the buffer and creates a batch and commit to DB. Adding OM request to doubleBuffer and swap of buffer are synchronized methods.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	OzoneManagerDoubleBuffer.Builder	Builder for creating OzoneManagerDoubleBuffer.

Method Summary

Modifier and Type	Method	Description
void	acquireUnFlushedTransactions(int n)	Acquires the given number of permits from unFlushedTransactions, blocking until all are available, or the thread is interrupted.
void	add(OMClientResponse response, org.apache.ratis.server.protocol.TermIndex termIndex)	Add OmResponseBufferEntry to buffer.
void	awaitFlush()
void	flushTransactions()	Runs in a background thread and batches the transaction in currentBuffer and commit to DB.
static OzoneManagerDoubleBuffer.Builder	newBuilder()
void	resume()
OzoneManagerDoubleBuffer	start()
void	stop()	Stop OM DoubleBuffer flush thread.
void	stopDaemon()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

newBuilder

public static OzoneManagerDoubleBuffer.Builder newBuilder()

start

public OzoneManagerDoubleBuffer start()

acquireUnFlushedTransactions

public void acquireUnFlushedTransactions(int n)
                                  throws InterruptedException

Acquires the given number of permits from unFlushedTransactions, blocking until all are available, or the thread is interrupted.

Throws:

InterruptedException

flushTransactions

public void flushTransactions()

Runs in a background thread and batches the transaction in currentBuffer and commit to DB.

stop

public void stop()

Stop OM DoubleBuffer flush thread.

stopDaemon

public void stopDaemon()

add

public void add(OMClientResponse response,
 org.apache.ratis.server.protocol.TermIndex termIndex)

Add OmResponseBufferEntry to buffer.

resume

public void resume()

awaitFlush

public void awaitFlush()
                throws InterruptedException

Throws:

InterruptedException